package de.graph.common;

/**
 * An edge links two vertices. 
 *
 * e.g. source ---label---> target.
 */
public interface Edge extends Element {

	/**
	 * Return the vertex on the tail of the edge.
	 * 
	 * @return the tail vertex
	 */
	public Vertex getTargetVertex();

	/**
	 * Return the vertex on the head of the edge.
	 * 
	 * @return the head vertex
	 */
	public Vertex getSourceVertex();
}
